Treatment of polymerizable petroleum distillates



w. T. HANCOCK Filed Jan. 22, 1'940 Oct. 28, 1941.

' TREATMENT 0F POLYMERIZABLE PETROLEUM DIsTILLATEs Patented Oct. 28, 1941 UNITED STATE;

s f OFFICE TREATMENT oF POLYMEBIZABLE PETRO- LEUM DIsTILLATEsL WilliamT. HancoclrLong-Beach, Calif; n t Application January 22, 19210,. Serial No. 315,010

l 13 claims; (c1. issy- 147) lA more complete understanding of various This invention relatesgenerally to the treatment of polymerizable petroleum hydrocarbons by the action of adsorptive material, and is particularly concerned with improvements in processes of y the general type disclosed in Patent Number 2,162,715'issued to me June 20,- 1939 on Process for refining cracked petroleum distillate.

I n accordance with the method employed in the.

patented as well as present processes, heatedy pressure distillate is subJ'z-:fctedA to polymerization above contemplates mixing the polymerized dis-j tillate and heated higher boiling oil under pressure in 'a flow line or mixing chamber, and then ash-vaporizing at least a portion of the gasoline content of the distillate by discharging the mixed oils into a vaporizing zone maintained under relduced pressure." According .to certain aspects of, v the present process, the polymerized vdistillate is delivered, with or without pressure reduction, into a'n enlarged mixing zone and therein contacted with the heated higher boiling oil and subjected to vaporization by the heat contained in that oil. Preferablyv the vaporized distillate is caused to ow upwardly in intimate contact with the higher boiling solvent oil in the mixing zone, as bymaintain-y ing aA continuous downward circulationpf the solvent oil in the path of the rising vapors. Heat Lis supplied to the solvent oil by continuously cir-V culating the oil between the mixing .chamber and an .external heat source, such as a tubular heater.

The invention further contemplates, when necessary or desirable, subjecting the hydrocarbonsivaporized from the higher boiling oilA as described, to second stage polymerization `and treatment with heavier oil. The initially poly-v merized hydrocarbons may be passed, either in liquid or Vapor phase, through'a second polymerizing zone containing adsorptive material, then ad-v "point of about 425 F., is introduced to the, system features and objects` of the invention, aswell as the :operation cfa typical and illustrative system embodying the invention, Will be had from the 4, following detailed description, throughout which reference is hadto the accompanying drawing showing suchtypical system diagrammatically andin flow sheetform.

The polymerizable hydrocarbon to be treated, for example, lpressure distillate having an end through line I0. Where the distillate is not preheated to -properpolymeri'zing temperature, the distillatemay bepassed through heater Il and therein heated'to a temperature of at least 200 F.

` and preferably higher, toV around 325 F. to 350 F.

Whenotherwise preheated, the distillate may be discharged from line I0 through line I2 for treatment in the rst polymerizing zone. The heated pressure distillate is introduced through line I3 'to' a' heat-insulated polymerizing chamber I4 containing .a body I5 of adsorptive material ofthe character above mentioned, the distillate flowing verticallyf'through the chamber in direct and intimate contact with the adsorptive material, and tliusz.v undergoing polymerization to convert its gum-forming and a large percentage of sulphurcontaining compounds, to polymerized condition.

The-pressure distillate stream', containing thev polymerized compounds, is discharged from the fpolyrnerizing zone through line I6 and is introduced into the lower portion of a heat insulated.

y contactorgenerally indicated at II. The distillate may flow from the polymerizing zone to the contactor either with or Without pressure reduction,

' as may be controlled by valve I8, it generally being preferred to maintain sufficient pressure on the distillate during polymerization that at least the major portion of the distillate will remain in liquid phase at the temperature to which the distillate fis'preheated. Ordinarily 'the heat transmitted mixed with heated higher boiling oil in a second 1 zone, and finally subjected to fractionation 0r condensation,

from the higher boiling' solvent oil, as later described," will be sufficient to vaporize the gasoline fractions. in vthe pressure distillatev at the polymerizing pressure, although wherever desired,

"vaporization of the gasoline fractions may lbe flacilitated by some pressure reduction at the valve The polymerized distillate stream flows fromline l. I6 into a body I9 of higherv boiling oil, for example vgas oil, fuel oil or a crude oil with or without gasoline content, maintained Within the lower mixing chamber I'Iaof the contactor I'I. If desired, .the higher boiling oil maybe maintained ata mimmum Alevel L within the mixing chamber by suitable means such as a liquid level control, diagrammatically indicated at 20, having an operating connection 2| with a valve 22 in the outlet line 23. The higher boiling oil is taken' from asuitable source, such .as an accumulator 24, through` line to a heater 26 wherein the oil is heated to a temperature suiciently high to elTect vaporization of the gasoline fractions in the pressure distillate. This temperature ordinarily will be in excess of 300 F. and preferably in the neighborhood of from 500 F. to 600 F. Leaving the heater 26, the higher boiling oil enters the mixing chamber of the contactor through line Y21.

is maintained between the heater andmixing chamber, the circulation being conducted through Thus .a continuous circulation of the'higher boilingoil ybody 43 of higher boiling oil being continuously circulated from the heater 44 through line 45,

, l and returned to the heater through line 45, accuaccumulator 24 in order to stabilize the flow andH n to permit removal `0f gums and other 'impuritiesv left from the pressure distillate in the heavier oil,

through line 28. The flow through line 28 may be substantially continuous, under control of a regulator 29 that maintains a liquid -level in the accumulator, and the system is thus continuously freed of a portion of the gums and impurities carried in and settling to the bottom ofthe heavyoil, as well as any excess of heavy oil resulting from the accumulation of higher boiling and unvaporized ends of the pressure distillate. Makeup solvent oil vmay be fed to the system'through line 3U at suincient rate to prevent, by dilution of the oilbeing circulated, excessive accumulations of gums and polymers.

If desired, the mixing chamber 11a may contain suitable means for causing the rising pressure'distillate stream to be divided and thus'subjected to more intimate contact with the heavyA oil, as by providing a series of screens 3| above the point of entry of thev distillate. Upon being admixed with and during the course of its flow upwardly in the higher temperature solvent oil, the pressure distillate becomes heated to a temperature suiciently high to vaporize at leastits gasoline content, the vapors asv they are formed passing upwardly through the heavier oil to the upper interior of the contactor. The vapors may be subjected to reux condensation within a dephlegmating zone 11b, so that the heavierthan-,gasoline ends are continuously condensed and returned to the body I9 of heated solvent oil. The dephlegmating zone I1b may contain a series of perforated plates lor bubble trays 32, andv may be operated with or without reflux'rrom an extraneous source. Preferably, however, a portion of the circulated higher boiling oil stream is introduced through line 33 to the upper interior of the dephlegmating Zone for the purpose of securing a final and down-'flowing contact with the rising pressure distillate vapors.

Leaving the contactor I1, the gasoline hydrocarbons are taken through line- 34 to be condensed or subjected to further treatment, as may.

be necessary or desirable depending upon the characteristics of the pressure distillate and the completeness with which the polymerizable or sulphur containing impurities have been removed in the contactor I1. In the'treatment of some distillates it may bey desirable to again sub-` ject the gasoline hydrocarbons to polymerization' and treatment with heated heavier oil,.and for this purpose the hydrocarbons may be taken from line 34 into a second polymerizing'zone 35 and passed downwardly through adsorptive ma- `mulator 24 and lines 25 and 41.

An independent heater 44 is shown to be provided for the oil being l, -circulated through contactor 42, in order to permit the maintenance of different temperatures in the contactors, and also different circulation rates if desired.

terial 36y as in the rst described polymerizinglv zone. In this second Vstage polymerization the The gasoline fractions of the pressure distillate, and perhaps some heavier ends, are adrnixed with the higher boiling oil in contactor 42 all as previously described, and the vapors discharged through line 48 for nal fractionation and condensation. As in the iirst contactor, the vapors may be subjected to dephlegmation within an upper section 42a offthe contactor, or treated with a down-flowing stream of the heated heavier oil introduced through line 49. As a typical method for subjecting the treated vapors to final con-Y densation, the vapors are shown to be discharged' through line 48 to a fractionating column 50 from which any heavier-than-gasoline ends are withdrawn through line 5i. The vapors flow through line 52 to a final condenser '53 from` which the condensate passes to a receiver 54.

As will be understood, the rate of circulation of the heated heavier oil through the mixing zone will be dependent upon the rate of pressure distillate flow and the relative ,temperatures of the two oils. Ordinarily the rate of solvent oil circulation Willbe at least two or three times that of the pressure distillate flow, and will be suicient to provide the amount of heat necessary to Vaporize the full gasoline content of the distillate. Where the pressure distillate is substantially entirely in liquid phase upon being introduced to the mixing chamber, a greater rate of heat supply by the heavier oil is required for vaporization of the distillate. If the polymerized distillate pressure be partially reduced at. or in advance of the pressure distillate.

I claim: l. The process of treating heated cracked petroleum distillate containing a gasoline raction, that includes subjecting the distillate to polymerization by contacting it with adsorptive Inaterial in a polymerizing zone, maintaining within an enlarged mixing zone a quantity of heated oil having a considerably higher boiling range'thansaid gasoline fraction, introducing the distillate from said polymerizing Zone into the mixing zone and therein intimately comingling' said higher boiling oil and the polymerized distillate at av ten'lperaturel above the vaporizing temperature Vof gasoline fraction at the pressure in the mixing zone, said temperature also being above the... temperature of the distiuatabeing introduced'to the'mixing zone, flowing the Vdistillate upwardly through the higher boiling oil and'therebycaus-"l' v ing polymerized and sulphur-containing bodies in"- the distillate to become retained in the higher 2;. TheI process of'treating' heatedycrackedlpee.

troleum distillate containing a gasoline fraction,

that includes, subjectingthe? distillate to poly.v

merization by contactingl it with adsorptive ma-V terial inr a polymerizingzone, maintaining Within* anenlarged mixing Zonek a body of independentheatedoil'` having a considerably'- higher 'boiling range than saidgasoline fraction, introducing' the distillate from said polymerizing zone into said? body' ofoil below` the surface thereof and* thereby intimatelyv corningling said` higher boil-V ing oil` and: thevr polymerized' distillate-at a temperature abovethe vaporizingvtemperature of said gasoline fractionat ther pressure in thev mixing zone; ii'owing the distillate upwardlyl through thei higher boiling oil and thereby-causing polymerized and sulphur-containing bodies in thedistil-` lateto become retained in the higher boiling'oil,- removing the -vaporizedgasoline fraction from'- the higher boiling oil and subjecting the removed vapors to condensationgand removing the unvaporized higher boiling oil from said mixingzone;

3. The process oftreating-heated crackedipetroleum distillatecontaining a gasoline fraction, thatl includes subjecting they distillate to polymerization by contacting it with adsorptivematerial' in a polymerizing- Zone; maintaining Within an enlargedmixing zonea down-flowing streamr of heatedoilhaving aL considerably higher boilingv range than said gasoline fraction; introducingv the distillate from said polymerizing zone intosaid stream and thereby intimately cominglingV saidihigherl boiling oil and the polymerized distillateatl a temperature above thevaporizingtemperature of said gasoline fraction at the presc inter-said; bodyl of oilbel'owy the surface.. thereofv y and therebyf intimately comingli'ng saidl higher' sure in the mixing Zone, saidtemperature als@ being above the temperature ofz the distillate beingintroduced to the-mixing Zone flowing the distillate upwardly through saidstream of higher boiling oil andi thereby causingl polymerized and' sulphur-containing bodies in the distillateto` become retained inthe Ahigher vboilingjoil; removing the vaporizedl gasoline fraction from the higher] boilingl oil and subjecting the-removed vaporsto condensation, andi separately removingv4 the unvaporized; higher; boiling oil from said mixing zone.

4. The processof treating-.heated crackedpe troleum-distillate containing-a gasoline fraction, that includes subjecting/the distillate to polymerization-by contacting it with adsorptive Ina-- terial in a'lpolymerizing zone, maintaining Within l an enlarged mixingzone al quantity-fof an independent heated oil having aconsiderablyhigherboilingvrange thansaid gasoline fraction, introducing the distillate from said polymerizing zone into the mixing zone and therein intimately comingling said higher boiling oil and the polymerized distillate at a temperature above the vaporizing temperature of said gasoline fraction at the pressure in the mixing Zone, owing the i'n'g-v zone, andi yreturning-r then lieatedl oil to sal'd mixing'zone. l y

' 5i.' The processv of? treating heated cracked pe'-A troleum distillate containing ai gasoline. fractiorn` that includesy subjecting -tlrief distillatey topolymerization by contacting itl-with: adsorptive materia1 in a polymerizi'ngj zone,v maintaining within, ain/enlarged mixing' zonefa body of an' independentlieated` oil having a considerably higherb'oit-` ingL rangethansaidf gasoline` fraction, introduc-A ing"`l the distillate from said' polymerizing Zone;

boilingfoil and the polymerized distillate'. at a'.

. temperature above'the vapori'zing. temperaturefof.l

said-4v gasoline fraction` at the pressure"l ink the" mixing zone, owing the distillate: upwardly throughfthehigher boiling oilandi thereby caus-A ing polymerized andi sulphur-containing' bodies'.v in thegdistillateto become retained in thel highen boiling oil;A removing thev vaporized. gasoline: fraction from: the higher boiling` oil'i and subj'ect-. ing thei removedl vapors to: condensation, passingr th'eiunvaporized higherrboiling oil .from said ingfzonethrough a-heating zone, and. returning-L' the heated oil to.- saidf mixing zone.-

` 6.' Theaprocessuoi treating.heatedlcrackedpeef l troleumadistillate containingal gasoline fraction; that includes subjecting the distillate.y tol poly-1.1 mer-ization by contacting it Withadsorptivermai terial in a polymerizingi Zone, maintaining.: within anienlargedv mixing Zonel a down-owingstream.'v of-an independent heated. oilhav-ing a: consider:- ably;rr higher boiling range than'. said: gasoline.

fraction; introducing the distillate from saida y polymerizingl zone-into said stream and: therebyr intimately. comingling.- said? higher boiling; oillandr the lpolymerized distillate'k ati a temperatureabove the -vaporizing temperature off saidagasolinetfraci-v' tion-at'fthe pressure' inlthe mixingszone, flowing; v

thedistillate upwardly through' said? streamiA of: higherj boiling oili and` thereby-l ca-using: polymer".- izedi' and-sulphurcontainingf bodies inv the dis;- tillate' to become retained in: the higher. boiling-3 oil; removing the vaporizedi gasoline kfractions fromi the higher boiling: oil.r and: subjecting'. the

removedvapors to condensation; passing the-unv, vaporized'higher boiling :oil vfrom saidrnixing.zonet` through' a-heating zone, and returningstheheated:` Y

oiltosaid mixing zone. v

'7; The process off treating cracked petroleum'..

distillate that includes; subjecting. heatedcra'cked;

distillate. containing a; gasoline `fraction tov poly, merizati'on by passing: the distillate through a body ofi' adsorptive material, heating; within# ai, heating: Zone an1.oil having a considerablyfhi'g-her" boiling-:range r than said gasolina fraction, mixing: said vrdistillate after passage through" saidiadsorpetive material and While heated, vii-tha substan-l tia-lly-;large quantity ofthe heatedvheavieroil, vaporizing, saidgasolme-fractiorr from the heavier? oil in a vaporizing zone, leaving polymerized and sulphur-containing constituents of the distillate in the heavier oil, condensing the vaporized gasoline fraction, passing the unvaporized heavier oil from said vaporizing zone through said heating zone, and then mixing the 'resulting heated oil with the polymerized distillate to again use the heated oil to remove polymerized and sulphurcontaining constituents of the distillate.

8. The process of treating cracked petroleum distillate that includes, subjecting heated cracked distillate containing a gasoline fraction to polymerization by passing the distillate through a bodyy of adsorptive material, heating Within a heating zone an oil having a considerably higher boiling range than said gasoline fractiongmixing said distillate after passage through said adsorptive material and While heated, with a substantiallyrlarge quantity of the heated `heavier oil,

vaporizing said gasoline fraction from the heavier oilin` a vaporizing Zone, leaving polymerized and sulphur-containing constituents of the distillate in the heavier oil, condensing the vaporized gasoline fraction, passing the unvaporized heavierA oil from said vaporizing zone through an enlarged accumulator zone and through said heat-A f ing zone, and then mixing the resulting heated oil with the polymerized distillate to again use the heated oil `to remove polymerized and sul-I said distillate after passage through said adsorptive material and While heated, with a substantially large quantity of the heated heavier oil, vaporizing said gasoline fraction from the heavier oil in a vaporizing zone, leaving polymerized and sulphur-containing constituents of the distillate in the heavier oil, condensing the vaporized gasoline fraction, removing from the unvaporized heavier oil impurities retained therein from the distillate, passing the heavier oil through said heating zone, and mixing the resulting heated oil with the polymerized distillate to again use the heated oil to remove polymerized and sulphurcontaining constituents of the distillate.

10. The process of treating cracked petroleum distillate that includes, subjecting heated cracked distillate containing a gasoline fraction to polymerization by passing the distillate through a body of adsorptive material, heating within a heating zone an oil having a considerably higher boiling range than said gasoline fraction, mixing said distillate after passage through said adsorptive material and while heated, with a substantially large quantity of the heated heavier oil, vaporizing said gasoline fraction from the heavier oil in a vaporizing zone, leaving polymerized and sulphur-containing constituents of the distillate in the heavier oil, condensing the vaporized gasolinefraction, removing the unvaporized heavier oil from said vaporizing zone, adding fresh oil to the heavier oil, passing the removed heavier oil through` said heating zone, and then mixing the resulting heated oil with the polymerized distillate to again use the heated oil to remove polymerized and sulphur-containing constituents of the distillate.

. 11. The process Aof treating cracked petroleum distillate that includes, subjecting heated cracked CII distillate containing a gasoline fraction topoly-` merization by passing the distillate through a body of adsorptive material, continuously heating anoil having a considerably higher boiling range than said gasoline fraction, mixing said distillate after passage through said adsorptive material and while heated, with a substantially large quantity of the heated heavier oil, Vaporizing said gasoline fraction from the heavier oil in a vaporizing Zone, leaving polymerized and sulphur-containing constituents of the distillate in the'heavier oil, condensing the vaporized gasoline fraction, and removing from said vaporizing zone and again mixingvwith the polymerized distillate a continuously circulated stream of said heavier oil to again use the heated oil to remove polymerized and sulphur-containing constituents of the distillate.

12. The process of treating cracked petroleum distillate that includes, subjecting heated cracked distillate containing a gasoline fraction to polymerization by passing the distillate through a bodyy of adsorptive material, continuously heating an oil having a considerably higher boiling range than said gasoline fraction, mixing said distillate after passage through said adsorptive material and while heated, With a substantially4 large quantity of the heated heavier oil, Vaporizing said gasoline fraction from the heavier oil in a vaporizing Zone,` leaving polymerized and sulphur-containing constituents of the distillate in the heavier oil, condensing the vaporized gasoline fraction, removing from said vaporizing zone and again mixing with the polymerized distillate a continuously circulated stream of said heavier oil, separating residual bodies from said circulated stream of heavier oil, and adding fresh oil thereto.

13. The process of treating heated cracked petroleum distillate containing a gasoline fraction, that includes subjecting the distillate to polymerization by contacting it With adsorptive material in a polymerizing zone, introducing the distillate from said polymerizing zone into an enlarged mixing zone, passing oil having a considerably higher boiling range than said gasoline fractionl through a heating zone and discharging the heated oil into the mixing Zone at a temperature higher than the temperature of the distillate being introduced thereto and above the 

